Mature size & growth rate

How big does Brunnera macrophylla (Brunnera macrophylla) get?

Also called Siberian bugloss, Large-leaved brunnera.

More about brunnera macrophylla

About Brunnera macrophylla

Brunnera macrophylla · also called Siberian bugloss, Large-leaved brunnera · flowering

The species Siberian bugloss, a tough, clump-forming shade perennial with large, plain green heart-shaped leaves and clouds of tiny blue forget-me-not flowers in mid to late spring. An easygoing woodland groundcover, the green-leaved species is more sun- and drought-tolerant than its silvered cultivars and self-seeds gently to colonise moist, shaded ground.

Mature size: 30-45 cm tall and 45-60 cm wide (about 12-18 in tall, 18-24 in wide)

Watch for — Slug and snail grazing: Tender new growth in damp shade is grazed by slugs and snails. Use barriers or wildlife-safe controls.

Indoor size vs how big it gets in the wild

Brunnera macrophylla stays fairly low but widens over time — it spreads into a bigger clump by offsets, runners or rhizomes rather than shooting upward. Indoors and in a pot, expect 30-45 cm tall and 45-60 cm wide (about 12-18 in tall, 18-24 in wide). A pot, your light levels and a little pruning are what set the final size in a home, far more than the plant's theoretical potential.

Size here is about width, not height: the plant builds an ever-wider clump or sends out plantlets and runners while staying relatively short.

Growth rate and years to mature

Brunnera macrophylla is a moderate grower. Realistically, expect three to six years to reach mature indoor size, gaining a steady amount each growing season. Its feeding profile backs this up: low feeder. a spring application of compost or balanced slow-release fertiliser is ample. this undemanding species rarely needs more.

Want this turned into the right next pot at the right moment? The pot size calculator and the brunnera macrophylla repotting guide cover when and how much to size up — pot size is one of the biggest levers on how fast brunnera macrophylla grows.

How to keep brunnera macrophylla smaller

You are not stuck with the maximum size. For brunnera macrophylla specifically, these are the levers, in order of impact:

Divide the clump every year or two — splitting brunnera macrophylla is the main way to control its spread and refresh it.
Remove runners, plantlets or offsets as they appear if you want it to stay a single tight clump.
Keep it slightly pot-bound; a snug pot naturally limits how wide the clump can get.

The keep-it-smaller method, step by step

Lift the whole plant. Slide brunnera macrophylla out of its pot in spring when the clump has filled it.
Split the clump. Tease or cut the rootball into two or more sections, each with healthy roots and growth.
Repot one division. Put a single division back in the original pot to reset it to a smaller size; pot or give away the rest.
Remove offsets as they form. Through the year, detach new runners or pups to stop it spreading again.

How to grow brunnera macrophylla bigger or faster

If you want it to fill the space sooner, push the conditions rather than hoping — for brunnera macrophylla the accelerators are:

Give it a wider pot and let the clump fill it — width is exactly how this plant gets bigger.
Brighter light speeds up clump and offset production noticeably.
Leave plantlets and offsets attached and feed through the growing season for the fastest spread.

Light is almost always the ceiling. The brunnera macrophylla light requirements page covers exactly how bright a spot it needs to grow at its potential instead of stalling.

When brunnera macrophylla outgrows the room (or the pot)

"Too big" usually arrives as one of these signs for brunnera macrophylla:

The clump bulging over the pot rim or splitting the pot — the cue to divide, not to find a bigger room.
A dense centre that goes bare or tired while the edges keep spreading.
Runners or offsets escaping across the shelf or into neighbouring pots.

If it is the pot rather than the room, it is a repotting job, not a goodbye — see the brunnera macrophylla repotting guide. If you want more of this plant instead of a bigger one, the brunnera macrophylla propagation guide turns prunings into new plants.

Brunnera macrophylla size — frequently asked questions

How big does brunnera macrophylla get?

Brunnera macrophylla reaches 30-45 cm tall and 45-60 cm wide (about 12-18 in tall, 18-24 in wide) when grown indoors. Size here is about width, not height: the plant builds an ever-wider clump or sends out plantlets and runners while staying relatively short.

Is brunnera macrophylla slow or fast growing?

Brunnera macrophylla is a moderate grower. Expect three to six years to reach mature indoor size, gaining a steady amount each growing season. Brunnera macrophylla stays fairly low but widens over time — it spreads into a bigger clump by offsets, runners or rhizomes rather than shooting upward.

How long does brunnera macrophylla take to reach full size?

Roughly three to six years to reach mature indoor size, gaining a steady amount each growing season. Light, pot size and feeding move that timeline more than anything else.

How do I keep brunnera macrophylla smaller?

Divide the clump every year or two — splitting brunnera macrophylla is the main way to control its spread and refresh it. Remove runners, plantlets or offsets as they appear if you want it to stay a single tight clump. Keep it slightly pot-bound; a snug pot naturally limits how wide the clump can get.

How can I make brunnera macrophylla grow bigger or faster?

Give it a wider pot and let the clump fill it — width is exactly how this plant gets bigger. Brighter light speeds up clump and offset production noticeably. Leave plantlets and offsets attached and feed through the growing season for the fastest spread.